Greatwyrm
Been here a while...
I'll take this to mean two things:
1. DDI is a phenomenal success
2. Books aren't selling as well as expected
Right now, Monster Manual 2 is at #10 on the Amazon Sci-Fi/Fantasy bestseller list. Many authors would kill for that level of failure.
A third thing can be sort of deducted - they need more money NOW, and their need is sufficiently great to force them to ruin the sales of one flagship product (PH3) a year in advance in order to push another flagship product (DDI).
Seriously, how many people will actually buy PH3 if complete parts thereof will be available on DDI (and, consequently, on pirate sites) for a year or so?
I'd say plenty of people would. The three core books sold just fine after pdfs of each appeared on file sharing networks. Actually, the initial marketing was so lackluster, I know more than one person who was convinced to buy-in only after seeing the pdfs.
And assuming PH3 will be similar in size to PH2, they'll only be releasing a little less than half of it in previews. I really don't think that'll cause much of an issue if people bought the core books when they had complete pdfs to begin with.
In other news, I have trouble seeing DDI as a flagship product. Maybe a companion product, but DDI just can't carry the brand by itself. I'm not saying that as a negative (I enjoy DDI), just that its probably not intended to be in that role.